Eye Examination Instruments

Eye Examination Instruments

A complete eye examination involves the use of many pieces of equipment and several instruments. During your thorough eye examination in Location, many diagnostic tests will be performed. The following are some of the instruments used in our office with descriptions of what they do:

Digital Retinal Camera: A digital retinal camera, also called a fundus camera, is used to produce high quality diagnostic images of the interior of the eye.

Phoropter: A phoropter is an instrument that allows Dr. Dille to precisely determine your numerical prescription for glasses or contacts. Typically, the patient sits behind the phoropter and looks through it at an eye chart. Dr. Dille then changes lenses and other settings while asking the patient for feedback on which settings give the best vision. This is repeated with several different settings until your exact prescription is found.

Auto-refractor: An auto-refractor is a computerized instrument used to measure a patient’s refractive error. This is achieved by measuring how light is changed as it enters a person’s eye. The automated refraction technique is quick, simple and painless. The patient takes a seat and places their chin on a rest. One eye at a time, they look into the machine at a picture inside. The picture moves in and out of focus as the machine takes readings to determine when the image is on the retina. Several readings are taken which the machine averages to form a prescription.

Slit Lamp: A slit lamp is a microscope with a light attached that allows Dr. Dille to closely examine the eye. This instrument is used to view structures of the eye such as the cornea, iris and lens. However, with special lenses, it is possible to examine the back of the eye as well.

Manual Keratometer: A manual keratometer measures the curvature of the cornea. It is often used to measure and diagnose conditions such as astigmatism, keratonus, corneal scarring and corneal distortion. A keratometer is commonly used to fit contact lenses as well.

Tonometer: A tonometer is used to measure the pressure of the eye and can help detect glaucoma.

Retinoscope: A retinoscope is a handheld device used to determine the refractive power of the eye by observing the lights and shadows on the pupil when a mirror illumines the retina. It is also useful for determining how well the eyes work together, accommodate, to see clearly.